1. Field of the Invention
The present invention relates to systems and methods for remediating water, and, more particularly, to such systems and methods that use aquatic plant cultures to remediate water.
2. Description of Related Art
Attached algal plant growth in shallow water is widely termed periphyton. The utilization of cycles of periphyton culturing and harvesting has proven to be an all-natural method to remove nutrients from polluted water. Compared with wetland treatment systems, periphyton filters have repeatedly demonstrated a removal of 100 to 1,000 times more nutrients per unit area. Among the work in the area can be included patents issued to one of the inventors of the present invention (KJ): U.S. Pat. Nos. 5,527,456; 5,573,669; 5,591,341; and 5,846,423.
High nutrients are a problem in global surface water because they support massive phytoplankton cultures, blocking light from rooted plants, which are an important habitat for a diverse and stable aquatic ecosystem.
The idea of culturing aquatic plants is ancient and has been practiced worldwide for centuries, mostly for food and fertilized production. Floating aquatic culture systems have been proposed for kelp production for energy purposes.
A floating aquatic periphyton culture system for fresh water nutrient removal is the “Lilypad,” which comprises a 40-ft-diameter fiberglass-foam composite structure, with an axial flow pump and speed controller effecting radial horizontal flow. The system was operated in a public pond for 1.5 years, and was found to achieve an average 1-ft reduction in heavy organic deposits in the pond after 1 year of operation, from which it was deduced that oxygen from periphyton photosynthesis oxidized organic sediments.
It would be desirable to provide an improved system and method for contaminant removal in bodies of water.